Decide what problem you are buying a solution for

Poor conversion may be caused by low-intent traffic, unclear product value, shipping surprises, mobile friction or unreliable tracking. A CRO programme cannot compensate for every acquisition problem. Start by separating acquisition quality from on-site friction and measurement defects.

Hire a CRO specialist when you have a functioning storefront and a practical path from research to implementation. Hire a broader ecommerce development partner if platform limitations, integrations or major theme work dominate the project.

• Conversion research: product and collection journeys, cart, checkout friction, mobile UX and behavioural evidence.
• Engineering: theme, apps, payments, integrations, performance and release QA.
• Acquisition alignment: landing-page promise, traffic source and customer intent.

What to put in your agency brief

Give every shortlisted agency the same baseline so you can compare proposals on substance, not slide design.

• Platform and markets, key product categories and any checkout constraints.
• Sessions, orders and revenue per session segmented by device and channel, with known tracking caveats.
• Current funnel from product view to add-to-cart, checkout and purchase.
• Internal capacity for design, development, analytics and approvals.
• Data access, privacy requirements and testing tools already in use.

A useful proposal has three phases

First, establish whether the data is trustworthy. Second, rank opportunities using evidence, impact, confidence and effort. Third, deliver changes with QA and a decision log. Each proposed experiment should name the audience, hypothesis, primary metric and conditions that would make the result inconclusive.

Low-volume stores often benefit more from research-led usability improvements than from a crowded A/B-testing calendar. Ask agencies how they adapt their method to sample size and seasonality.

• Request examples of inconclusive or unsuccessful tests and what the team learned.
• Confirm who implements winning variants and who owns code, analytics and tooling.
• Ask for business outcomes alongside micro-conversions.
• Require a plan to protect organic search, accessibility and page speed.

Red flags when comparing agencies

Be cautious of guaranteed percentage lifts before an audit, a plan based entirely on generic best practices, or reporting that celebrates clicks while ignoring orders and margin. A polished heatmap is not a measurement strategy.

The most useful partner will challenge your assumptions and tell you when a test cannot support a reliable conclusion.

Five questions for the shortlist

• What will you validate before running our first experiment?
• How do you determine whether traffic and order volume support a reliable test?
• Which problems belong to CRO versus engineering or acquisition?
• Who ships, tests and maintains the changes?
• How do you report a result that is inconclusive or negative?

Three buying scenarios that change the brief

High traffic, weak purchase completion: request a diagnosis of product clarity, delivery expectations and mobile friction before approving a testing backlog. Deliverable: ranked hypotheses and one measurable initial experiment.

Low traffic, high order value: frequent small A/B tests may be underpowered. Prioritise interviews, usability research and clearly documented improvements that can be monitored over a longer period.

Complex stack, unreliable order data: validate events, revenue values and consent handling first. An experimentation retainer cannot rescue decisions based on incorrect tracking.

Compare bids by separating research, experiment design, development, QA and reporting. Name the owner who approves a launch, can roll back a change and records what the team learned.